Hacker News new | ask | show | jobs
by exception 5649 days ago
Heh, yeah I still remember 6502 opcodes... 4C xx xx is jmp absolute, 20 xx xx is jsr (jump subroutine) absolute, A9 xx xx is load accumulator absolute, 8D store accumulator, 60 is rts... I could go on.

Typing shit in to the hex monitor for a few years will do that :)
1 comments
Someone 5648 days ago
A9 xx xx is load accumulator absolute

Make that A9 xx; The 6502 accumulator is 8 bits.

link
exception 5648 days ago
Thanks for the correction, you're right A9 is load immediate I was mixing it up with AD xx xx which follows as 8D is the equivalent store.

I wasn't saying that the accumulator was 16 bit though, rather that the load is from an absolute 16 bit address.

link